EFFECTS OF CASSIA SIEBERIENA   LEAF EXTRACTS ON THE INTESTINAL MOTILITY OF RAT

The in - vitro effects of methanolic extract (MCSL) and aqueous infusion (ACSL) of the leaves of C. sieberiena on the motility of the rat intestines were studied and compared with those of C. acutifolia (MCAL and ACAL) "Senna". All the extracts and infusion relaxed the ileum dose-dependently. Their effects were blocked by tolazoline, indicating that α-adrenergic receptors were involved. MCSL contracted the colon dose - dependently and was blocked by atropine(1.7x10 ^-8 M) and nifedipine (2.8x10 ^-10 M). ACSL contracted this segment at 2.0-8.0 mg/ml and relaxed it at 8.0-16.0mg/ml. Its relaxant effect was blocked by tolazoline (1.0x10 ^-6 M), indicating the involvement of α - adrenergic receptors . MCAL had a slight relaxant effect on the colon, while ACAL contracted it dose dependently and was blocked by promethazine (3.1x10 ^-8 M) and nifedipine (2.8 x 10 ^-8 M), indicating that H₁ -receptor stimulation and increased intracellular calcium ion concentration are involved. MCSL was more potent than ACAL, while ACSL and ACAL were equipotent in contracting the colon. With proper processing C. sieberiena can be substituted for C. acutifolia .